Medical Marijuana for Arthritis Sufferers
Research shows that, among other things, cannabis eases chemotherapy-induced nausea and loss of appetite, and relieves spasms in individuals with multiple sclerosis. Even so, pain relief is perhaps the most well-recognized and studied effect.
Several decades ago, scientists discovered that mammals, including humans, have a pain-regulating system (the endocannabinoid system) with receptors in nervous system tissue, immune cells and bone and joint tissue. These receptors respond to cannabinoids, a set of compounds that include endocannabinoids, which the body creates on its own; and phyto-cannabinoids, plant-based compounds found in marijuana that are very similar to endocannabinoids.
The best known cannabinoids are THC (delta-9-tetrahydrocannabinol, the psychoactive compound in cannabis) and CBD (cannabidiol, a major constituent of the plant thought to act as a sedative and reduce inflammation, nausea and convulsions). They have complex mechanisms, but in a nutshell, cannabinoids can reduce pain by acting on certain receptors.
Of the two main cannabis species – sativa and indica – sativa contains higher THC and lower CBD levels and produces a more euphoric “high.” Indica has higher CBD and lower THC levels and is used to aid sleep and ease pain.
Cannabinoids also seem to have a positive impact on some other pain medications. One study, in Clinical Pharmacology & Therapeutics in 2011, found that chronic pain patients using long-acting oxycodone or long-acting morphine who inhaled vaporized herbal cannabis experienced a significant decrease in pain – far more than with the opioids alone. Though the study was of just 21 patients, study author Donald I. Abrams, MD, professor of clinical medicine at the University of California, San Francisco, says it “suggests that cannabis has the potential to relieve pain and decrease use of opioids, which, unlike cannabis, are associated with major side effects.”
Evidence for Arthritis
Studies show it can be somewhat effective in treating pain from arthritis and related conditions. One meta-analysis of four randomized trials published as an abstract in the Annals of the Rheumatic Diseases, found that oral cannabinoids (cannabis oil) offered minimal to moderate improvement compared with placebo in individuals with musculoskeletal pain, including RA, back pain and fibromyalgia. Study author Janet Pope, MD, professor of medicine at the University of Western Ontario in Canada, notes that the results are not generalizable to smoking marijuana, and says, “The benefit was modest, and this was only studied for short periods of time.”
A 2011 British Journal of Clinical Pharmacology review examined 18 studies of smoked, oral and/or synthetic cannabis and concluded cannabis was safe and modestly effective in neuropathic pain (chronic pain that results from damaged or dysfunctional nerve fibers), and also had the potential to help treat RA and fibromyalgia pain. Additionally, cannabis has been shown to improve sleep – and a lack of sleep is known to exacerbate general pain and arthritis symptoms.
And cannabis holds promise for osteoarthritis (OA). “Joints have a complex endocannabinoid system and are able to produce their own endocannabinoids. But in disease states, such as with osteoarthritis, these endocannabinoids are broken down too quickly, so they can’t help with joint pain,” says Jason J. McDougall, PhD, associate professor in the departments of pharmacology and anesthesia at Dalhousie University in Halifax, Nova Scotia. In ongoing animal research, McDougall and his colleagues have found that by blocking certain enzymes or injecting cannabinoids into the joint, sensitivity and pain are reduced, leading McDougall to speculate that both endocannabinoid-targeting and cannabis-based treatments may hold new hope for individuals with OA.
Cannabis also may ease inflammation and affect immunity. In-vitro and animal studies have shown that both herbal and synthetic cannabinoids have the ability to suppress inflammation. Most recently, a Biological & Pharmaceutical Bulletin study in 2011 revealed that six different cannabinoids inhibited the activity of COX-2 enzymes, which play a role in arthritis-related inflammation. Other preliminary studies suggest cannabinoids may have immunosuppressive properties – including the ability to inhibit pro-inflammatory molecules called cytokines.
* as always please be sure to consult with a health professional to assess the risks and rewards of adding medicinal cannabis to your treatment program.